Shuttle-driving mechanism for sewing-machines.



No. 745,256. PATENTED NOV. 24, 1903. A. SPEAR. SHUTTLE DRIVING MECHANISM FOR SEWING MACHINES.

APPLICATION FIEED AUG. 31, 1901. RENEWED APR. 9, 1903. N0 MODEL.

n4: Npnms PETERS ca, PHOTO-LITHEL. WASHINGTON D. c.

i atented l fovember 24, 1903.

UNITED STATES PATENT OFFICE.

ARTHUR SPEAR, OF CHICAGO, ILLINOIS, ASSIGNOR TO J. P. GARDNER, OF

' CHICAGO, ILLINOIS.

SHUTTLE-DRIVING MECHANISM FOR SEWING-MACHINES.

SPECIFICATION forming part Of Letters Patent N0. 745, 256, dated November 24:, 1903. Application filed August 31,1901. Renewed April 9, 1903. Serial No. 151,922. (No model.)

To aZZ whom it may concern:

Be it known that I, ARTHUR SPEAR,a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Shuttle-Driving Mechanism for Sewing-Machines, f which the following is a full, clear, and exact specification.

My invention relates more particularly to that class of sewing-machines in which both the needle-bar and the shuttle are driven by rotary shafts connected together so that one will drive the other; and my invention has for its primary object to simplify and cheapen the construction and principal of operation of a machine of this character whereby it will be feasible and better adapted for embodiment in the form of a toy machine, while at the same time itwill be durable and effizo cient.

With these ends in view my invention con sists in certain features of novelty in the G011- struction, combination, and arrangement of parts by which the said objects and certain other objects hereinafter appearing are attained, all as fully described with reference to the accompanying drawings, and more particularly pointed out in the claim.

In the said drawings, Figure 1 is avertical 3o longitudinal sectional view of a part of a sewing machine frame embodying my improvements; and Fig. 2 is a detail sectional view, taken on the line 2 2, Fig. 1, looking in the direction of the arrows.

3 5 1 is the base of a sewing-machine frame which in the form of the invention shown in the drawings is of the toy Variety and designed to be set upon an ordinary table or any other support where it is desired to use the machine, and as a consequence pulley 2, which drives shuttle-shaft 3, is mounted at a sufficient elevation from the lower edge of the base 1 to avoid touching the table or other surface upon which the machine might be supported.

The shuttle-shaft 3, which may be connected to the shuttle (not shown) in the usual or any suitable way, is provided at a point within the standard 4 of the sewing-machine frame with a crank 5, and this crank is connected to a similar crank 6, formed on needle-bar lever 9and fits accurately within a cylindrical 6o guideway or bore 12, formed vertically in a guide-block 13, cast in or secured to thestandard l. I By the described means it will be seen that assuming the parts to be in the position shown 6 5 v in Fig. 2 and the shuttle-shaft 3 to be rotated toward the right the initial action of the lever 9 will be to swing laterally on its fulcrum 11 toward the right at the lower end and toward the left at the upper end, and I consequently the dead-centers will be passed,

and as the upper crank passes the dead-center it will be at the same time pulled downwardly by the endwise motion of the lever, and this downward movement will continue until the lower crank reaches the position diametrically opposite that shown in Fig. 2, the upper crank being at this instant also on dead-center; but in asmuch as the lower crank moves toward the left at this time the upper crank will be pushed toward the right laterallybeyond the dead-center before the upward thrust on the lever 9 takes place to a sufficient degree to cause the parts to look. It is-of course understood that during the'described movements of the cranks and lever the ballfulcrum 11 slides up and down in its guideway 12, which constitutes a perfect bearing and guide for the ball, whose wearing-surfaces are continually changing, and hence the fulcrum remains reasonably tight for a great length of time. It is also understood that the ball 11 should be of sufficient diameter to permit of the oscillation of the lever within the guideway 12, which latter is large enough to permit the end of the lever to be passed through it.

The pulley2 is driven bya crank-wheel 14, which may be journaled on a projecting end 15 of the needle-bar shaft 7 and held in place I00 by headed screw 16, wheel 14 being connected to pulley 2 bya suitable belt 17. This method of driving the shaft 3 is resorted to in order that the lower pulley 2 may be smaller than could be the case if it were utilized as the crank-wheel, it being understood that a larger wheel or pulley would necessitate a greater elevation of the shuttleshaft 3.

Those skilled in the art to which this invention relates will of course understand that the cranks 5 6 should be of equal throw, or else the fulcrum 11 should be so positioned with reference to the length of the lever 9 as to give one end of the lever a degree of oscillation equal to the crank of greater throw and the other end a degree equal to the throw of the other crank. In the example shown in the drawings the cranks being of equal throwthe fulcrum 11 is positioned at the midlength of the lever, and although it is continually changing its altitude or position with reference to the length of its guideway 12 the degree of oscillation never changes.

If desired, the loose pulley 14 may be provided with suitable means, such as set-screw 18, whereby it may be secured to shaft 7 should it be found desirable to drive pulley 2 by a belt from the ordinary treadle mechanism, so that wheel 14 in that event may be made to serve as a fly-wheel.

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is-

A shuttle-driving mechanism for sewingmachines comprising a frame constructed with a base, a standard having an arm and a fixed guide-block formed with a bore providing a guideway, a sl1uttle-operating shaft having a crank and journaled in the upper part of the base, a needle-bar-operating shaft having a crank and j ournaled in the arm of the standard, a lever having a ball-fulcrum working freely in the guideway of the fixed guide-block, means whereby the lever is connected with the shafts, and a wheel mounted on one of said shafts.

ARTHUR SPEAR.

\Vitnesses:

W. D. Gnoss, F. A. HOPKINS. 

